LOS ANGELES (CBS) — CBS News is reporting that Osama Bin Laden’s next target was the US rail system including targets in Los Angeles, New York, Washington and Chicago.

Bob Orr also reported that it appeared Osama Bin Laden was aiming to make a deadly attack around a date special to Americans, July 4th, New Year’s or Sept. 11.

Orr quotes sources familiar with some of the material seized from Bin Laden’s computers, files, dvds and documents.

The cache of material, says Orr, showed that Bin Laden was “desperate” to recreate another 9-11 type attack on the US.

It is not clear how far along the attack had been planned.

Homeland Security officials warned law enforcement agents around the county in February 2010 that al Qaeda planned to take down a major train that would fall into a valley or off a bridge. It’s not clear if the new documents reveal why that attack didn’t come off.

Officials call the cache of documents “a window into Bin Laden’s world” and invaluable to the combat against terror.